KR20230091832A - Method and apparatus for radio signal transmission and reception in communication system - Google Patents

Abstract

In one embodiment of a communication system, a method of operating a first communication node includes generating a first binary sequence and a second binary sequence, based on the first and second binary sequences and a BPSK operation, 2N elements Generating a first intermediate sequence having N elements based on an operation on elements of the first intermediate sequence, generating a first signal sequence composed of N elements, modulating and generating the first signal sequence mapping first modulation symbols to N subcarriers, and transmitting a first signal composed of the mapped first modulation symbols, wherein the first and second binary sequences have a maximum order It is generated based on generation polynomials having n+1, n is a natural number, and N may be a natural number having a value of 2n-1.

Description

Method and device for transmitting and receiving radio signals in a communication system

The present disclosure relates to a technology for transmitting and receiving a radio signal in a communication system, and more specifically, to a technology for improving transmission and reception performance of a radio signal in a communication system.

Along with the development of information and communication technology, various wireless communication technologies are being developed. Representative wireless communication technologies include long term evolution (LTE) and new radio (NR), which are defined in the 3rd generation partnership project (3GPP) standard. LTE may be one wireless communication technology among 4th generation (4G) wireless communication technologies, and NR may be one wireless communication technology among 5th generation (5G) wireless communication technologies. A wireless communication technology after 5G (eg, 6th generation (6G), etc.) may be referred to as a beyond 5G (B5G) wireless communication technology.

In one embodiment of the communication system, in order to access a wireless network, a user may perform serving cell identification after acquiring time/frequency synchronization with the network. The serving cell identification may be performed, for example, through physical cell identity (PCI) estimation using a predetermined synchronization signal. Each cell may have a different PCI and may transmit a synchronization signal including information for identifying the PCI (ie, a synchronization signal indicating the PCI). For an easy cell identification operation, cross-correlation characteristics between synchronization signals indicating different PCIs may be excellent, and variability of cross-correlation characteristics of all possible synchronization signal pairs may be low.

Meanwhile, the number of distinguishable PCIs may be limited according to a synchronization signal design method. In order to overcome this limitation and increase the number of distinguishable PCIs, in one embodiment of the communication system, cyclically distinct sequences are cyclically shifted to obtain linearly distinct synchronization. A method of generating a signal may be used. Sequences generated through circular movement in this way may not follow the cross-correlation characteristics of the original sequences. As a result, cross-correlation characteristics between the generated synchronization signal pairs may be deteriorated, and variability of the cross-correlation characteristics may increase. A technique capable of effectively increasing the number of discriminable PCIs while maintaining cross-correlation characteristics of synchronization signals and their variability may be required.

Matters described in this background art section are prepared to enhance understanding of the background of the invention, and may include matters that are not prior art already known to those skilled in the art to which this technique belongs.

An object of the present disclosure to achieve the above needs is to provide a signal transmission/reception method and apparatus for improving the performance of a cell identification operation based on a radio signal in a communication system.

In one embodiment of a communication system for achieving the above object, a method of operating a first communication node includes generating first and second binary sequences composed of 2N elements, the first and second binary sequences. s and binary phase shift keying (BPSK) operations, generating a first intermediate sequence consisting of 2N elements, based on operations on the 2N elements constituting the first intermediate sequence, Generating a first signal sequence composed of N elements, mapping first modulation symbols generated by modulating the first signal sequence to N subcarriers, and using the mapped first modulation symbols Transmitting a first signal consisting of, wherein the first and second binary sequences are generated based on generator polynomials having a maximum degree (p+1) and a first identifier for the first communication node. And, p is a natural number, and N may be a natural number having a value of (2 ^p -1).

Generating the first intermediate sequence may include generating first and second circular movement indices based on the first identifier, applying the first circular movement index to the first binary sequence, and the first binary sequence. 2 Applying the second circular shift index to a binary sequence, performing the BPSK operation on the sum of the first and second binary sequences to which the first and second circular shift indices are applied, and the BPSK operation It may include obtaining the first intermediate sequence corresponding to the result of.

Generating the first signal sequence may include multiplying 2k-th elements among the 2N elements constituting the first intermediate sequence by a first coefficient that is a real number, and the 2N elements constituting the first intermediate sequence. multiplying 2k+1th elements among the elements by a second coefficient that is a pure imaginary number, the 2kth elements multiplied by the first coefficient and the 2k+1th elements multiplied by the second coefficient performing a sum operation on , and obtaining k-th elements of the first signal sequence based on a result of the sum operation, where k may be an integer greater than or equal to 0 and less than N.

Generating the first signal sequence may include multiplying 2k-th elements among the 2N elements constituting the first intermediate sequence by a first coefficient that is a real number, and the 2N elements constituting the first intermediate sequence. multiplying a 2k+1th element among the elements by a second coefficient, which is a pure imaginary number, for the 2kth element multiplied by the first coefficient and the 2k+1th element multiplied by the second coefficient Performing a sum operation, performing a rotation transformation operation by a first angle on a complex plane with respect to a result of the sum operation, and performing a rotation transformation operation by a first angle on the complex plane, and based on the result of the rotation transformation operation, the kth of the first signal sequence. elements, wherein k may be an integer greater than or equal to 0 and less than N.

The first angle may be one of π/4, -π/4, 3π/4, or -3π/4.

The first signal may support up to (2N+1) ^two distinguishable values for the first identifier.

In one embodiment of the communication system for achieving the above object, the operating method of the first communication node is composed of first and second binary sequences composed of (N/2) elements, and M elements. Generating a third binary sequence that is, based on the first to third binary sequences and a binary phase shift keying (BPSK) operation, generating a first intermediate sequence consisting of (N / 2) elements generating first and second element groups each composed of (N/2) elements based on the first intermediate sequence; based on the first and second element groups, Generating a first signal sequence composed of N elements, mapping first modulation symbols generated by modulating the first signal sequence to N subcarriers, and using the mapped first modulation symbols Transmitting a first signal consisting of, wherein the first and second binary sequences are generated based on generator polynomials having a maximum degree (p-1), and the first to third binary sequences To each, first to third circular movement indexes determined based on the first identifier for the first communication node are applied, where p is a natural number and N is a natural number having a value of (2 ^p -2). And, M may be a natural number having a value of (N/2) or less.

Generating the first intermediate sequence may include determining the first to third circular movement indices based on the first identifier, applying the first circular movement index to the first binary sequence, the Applying the second circular shift index to a second binary sequence, applying the third circular shift index to the third binary sequence, and applying the first to third circular shift indices to which the first to third circular shift indices are applied. The method may include performing the BPSK operation on a sum of binary sequences, and obtaining the first intermediate sequence corresponding to a result of the BPSK operation.

The determining of the first to third circular movement indices may include determining a first variable g based on a value of the first identifier, and determining a second variable g based on the number of values that the first identifier may have. determining a variable Ω, and determining the first to third circular movement indices based on the first variable g, the second variable Ω and a first reference value t and one or more modulo operations. And, g, Ω, and t may be natural numbers.

The second circular movement index may be determined based on a t-modulo operation and an Ω-modulo operation for the first variable g.

The first signal may support up to (M×N×N) distinguishable values for the first identifier.

The (N/2) elements constituting the first element group are represented by k-th elements, and the (N/2) elements constituting the second element group are represented by (N/2+k)-th elements. elements, and the generating of the first and second element groups may include the first element based on k-th elements among the (N/2) elements constituting the first intermediate sequence. obtaining the k-th elements of the group, and the (N/2) elements of the second element group based on the k-th elements among the (N/2) elements constituting the first intermediate sequence. and obtaining +k)th elements, wherein the N elements constituting the first signal sequence include the (N/2) elements constituting the first element group and the second element group. It is configured to include the (N/2) number of elements, and k may be an integer greater than or equal to 0 and smaller than (N/2).

The (N/2) elements constituting the first element group are represented by (N/2-1-k)th elements, and the (N/2) elements constituting the second element group are It is represented by (N/2+k)-th elements, and the generating of the first and second element groups includes the k-th elements among the (N/2) elements constituting the first intermediate sequence. Obtaining the (N/2-1-k)th elements of the first element group based on, and the kth element among the (N/2) elements constituting the first intermediate sequence. obtaining the (N/2+k)-th elements of the second element group based on , wherein the N elements constituting the first signal sequence constitute the first element group. The first communication is configured to include the (N/2) elements and the (N/2) elements constituting the second element group, wherein k is an integer greater than or equal to 0 and smaller than (N/2). How nodes work.

The first modulation symbols mapped to the N subcarriers may form a centrally symmetrical structure around a first reference subcarrier of the N subcarriers.

The first signal may have only real components in the time domain.

In one embodiment of a communication system for achieving the above object, a first communication node includes a processor, and the processor includes a first communication node composed of (N/2) elements. 1 and 2 binary sequences, and a third binary sequence consisting of M elements is generated, and based on the first to third binary sequences and BPSK (Binary Phase Shift Keying) operation, (N / 2 ) generating a first intermediate sequence consisting of elements, generating first and second element groups each consisting of (N/2) elements based on the first intermediate sequence, Based on the first and second element groups, a first signal sequence composed of N elements is generated, and first modulation symbols generated by modulating the first signal sequence are mapped to N subcarriers; , and operate to cause transmitting a first signal consisting of the mapped first modulation symbols, wherein the first and second binary sequences are generated based on generator polynomials having maximum order (p-1). And, to each of the first to third binary sequences, first to third circular movement indices determined based on the first identifier for the first communication node are applied, where p is a natural number, and N is It is a natural number having a value of (2 ^p -2), and M may be a natural number having a value of (N/2) or less.

When generating the first intermediate sequence, the processor determines that the first communication node determines the first to third circular movement indices based on the first identifier, and assigns the first circular movement index to the first binary sequence. A movement index is applied, the second circular movement index is applied to the second binary sequence, the third circular movement index is applied to the third binary sequence, and the first to third circular movement indexes are applied. and further cause performing the BPSK operation on the sum of first to third binary sequences, and obtaining the first intermediate sequence corresponding to a result of the BPSK operation.

When determining the first to third circular movement indices, the processor determines that the first communication node determines a first variable g based on the value of the first identifier, and a value that the first identifier can have. determine a second variable Ω based on the number of s, and based on the first variable g, the second variable Ω and a first reference value t and one or more modulo operations, the first to third circular shifts indices, where g, Ω and t may be natural numbers.

The second circular movement index may be determined based on a t-modulo operation and an Ω-modulo operation for the first variable g.

The first signal may support up to (M×N×N) distinguishable values for the first identifier.

According to an embodiment of a method and apparatus for transmitting and receiving a radio signal in a communication system, performance of an estimation operation or an identification operation based on a radio signal transmitted and received between a transmission node and a reception node may be improved. A radio signal according to an embodiment of a method and apparatus for transmitting and receiving a radio signal in a communication system can support classification of more identification indices while using the same frequency resource. According to a radio signal according to an embodiment of a method and apparatus for transmitting and receiving a radio signal in a communication system, computational complexity for an estimation operation or an identification operation may be reduced. A radio signal according to an embodiment of a method and apparatus for transmitting and receiving a radio signal in a communication system may have lower transmission complexity while using the same frequency resource.

1 is a conceptual diagram illustrating an embodiment of a communication system.
2 is a block diagram illustrating an embodiment of a communication node constituting a communication system.
3 is a conceptual diagram illustrating an embodiment of a structure of a radio frame in a communication system.
4 is a flowchart for explaining an embodiment of a signal transmission/reception method in a communication system.
5A and 5B are conceptual diagrams for explaining a first embodiment of a radio signal structure in a communication system.
6A to 6D are conceptual diagrams for explaining first and second embodiments of a method for generating a radio signal in a communication system.
7A to 7H are conceptual diagrams for explaining a third embodiment of a radio signal generation method in a communication system.

Since the present disclosure can make various changes and have various embodiments, specific embodiments are illustrated in the drawings and described in detail. However, this is not intended to limit the present disclosure to specific embodiments, and should be understood to include all modifications, equivalents, and substitutes included in the spirit and scope of the present disclosure.

Terms such as first and second may be used to describe various components, but the components should not be limited by the terms. These terms are only used for the purpose of distinguishing one component from another. For example, a first element may be termed a second element, and similarly, a second element may be termed a first element, without departing from the scope of the present disclosure. The terms and/or include any combination of a plurality of related recited items or any of a plurality of related recited items.

It is understood that when an element is referred to as being "connected" or "connected" to another element, it may be directly connected or connected to the other element, but other elements may exist in the middle. It should be. On the other hand, when an element is referred to as “directly connected” or “directly connected” to another element, it should be understood that no other element exists in the middle.

Terms used in the present disclosure are only used to describe specific embodiments, and are not intended to limit the present disclosure. Singular expressions include plural expressions unless the context clearly dictates otherwise. In the present disclosure, terms such as "comprise" or "having" are intended to indicate that there is a feature, number, step, operation, component, part, or combination thereof described in the specification, but one or more other features It should be understood that the presence or addition of numbers, steps, operations, components, parts, or combinations thereof is not precluded.

Unless defined otherwise, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs. Terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with the meaning in the context of the related art, and unless explicitly defined in the present disclosure, they should not be interpreted in an ideal or excessively formal meaning. don't

A communication system to which embodiments according to the present disclosure are applied will be described. A communication system to which embodiments according to the present disclosure are applied is not limited to the content described below, and embodiments according to the present disclosure may be applied to various communication systems. Here, the communication system may be used in the same sense as a communication network.

Throughout the specification, a network refers to, for example, wireless Internet such as WiFi (wireless fidelity), portable Internet such as WiBro (wireless broadband internet) or WiMax (world interoperability for microwave access), and GSM (global system for mobile communication). ) or CDMA (code division multiple access) 2G mobile communication networks, WCDMA (wideband code division multiple access) or CDMA2000 3G mobile communication networks, HSDPA (high speed downlink packet access) or HSUPA (high speed uplink packet access) It may include a 3.5G mobile communication network, a 4G mobile communication network such as a long term evolution (LTE) network or an LTE-Advanced network, a 5G mobile communication network, a B5G mobile communication network (6G mobile communication network, etc.).

Throughout the specification, a terminal includes a mobile station, a mobile terminal, a subscriber station, a portable subscriber station, a user equipment, and an access terminal. It may refer to a terminal, a mobile station, a mobile terminal, a subscriber station, a mobile subscriber station, a user device, an access terminal, or the like, and may include all or some functions of a terminal, a mobile station, a mobile terminal, a subscriber station, a mobile subscriber station, a user equipment, an access terminal, and the like.

Here, a desktop computer capable of communicating with a terminal, a laptop computer, a tablet PC, a wireless phone, a mobile phone, a smart phone, and a smart watch (smart watch), smart glass, e-book reader, PMP (portable multimedia player), portable game console, navigation device, digital camera, DMB (digital multimedia broadcasting) player, digital voice digital audio recorder, digital audio player, digital picture recorder, digital picture player, digital video recorder, digital video player ) can be used.

Throughout the specification, a base station includes an access point, a radio access station, a node B, an evolved nodeB, a base transceiver station, and an MMR ( It may refer to a mobile multihop relay)-BS, and may include all or some functions of a base station, access point, wireless access station, NodeB, eNodeB, transmission/reception base station, MMR-BS, and the like.

Hereinafter, with reference to the accompanying drawings, preferred embodiments of the present disclosure will be described in more detail. In order to facilitate overall understanding in describing the present disclosure, the same reference numerals are used for the same components in the drawings, and redundant descriptions of the same components are omitted.

1 is a conceptual diagram illustrating an embodiment of a communication system.

Referring to FIG. 1, a communication system 100 includes a plurality of communication nodes 110-1, 110-2, 110-3, 120-1, 120-2, 130-1, 130-2, 130-3, 130-4, 130-5, 130-6). A plurality of communication nodes are 4G communication (eg, long term evolution (LTE), advanced (LTE-A)), 5G communication (eg, new radio (NR)) specified in the 3rd generation partnership project (3GPP) standard ), etc. can be supported. 4G communication may be performed in a frequency band of 6 GHz or less, and 5G communication may be performed in a frequency band of 6 GHz or more as well as a frequency band of 6 GHz or less.

For example, for 4G communication and 5G communication, a plurality of communication nodes may use a code division multiple access (CDMA)-based communication protocol, a wideband CDMA (WCDMA)-based communication protocol, a time division multiple access (TDMA)-based communication protocol, FDMA (frequency division multiple access)-based communication protocol, OFDM (orthogonal frequency division multiplexing)-based communication protocol, Filtered OFDM-based communication protocol, CP (cyclic prefix)-OFDM-based communication protocol, DFT-s-OFDM (discrete Fourier transform-spread-OFDM) based communication protocol, OFDMA (orthogonal frequency division multiple access) based communication protocol, SC (single carrier)-FDMA based communication protocol, NOMA (Non-orthogonal multiple access), GFDM (generalized frequency) division multiplexing)-based communication protocol, FBMC (filter bank multi-carrier)-based communication protocol, UFMC (universal filtered multi-carrier)-based communication protocol, SDMA (Space Division Multiple Access)-based communication protocol, etc. can be supported. .

In addition, the communication system 100 may further include a core network. When the communication system 100 supports 4G communication, the core network may include a serving-gateway (S-GW), a packet data network (PDN)-gateway (P-GW), a mobility management entity (MME), and the like. there is. When the communication system 100 supports 5G communication, the core network may include a user plane function (UPF), a session management function (SMF), an access and mobility management function (AMF), and the like.

Meanwhile, a plurality of communication nodes 110-1, 110-2, 110-3, 120-1, 120-2, 130-1, 130-2, 130-3, 130-1 constituting the communication system 100 4, 130-5, 130-6) may each have the following structure.

2 is a block diagram illustrating an embodiment of a communication node constituting a communication system.

Referring to FIG. 2 , a communication node 200 may include at least one processor 220, a memory 220, and a transceiver 230 connected to a network to perform communication. In addition, the communication node 200 may further include an input interface device 240, an output interface device 250, a storage device 260, and the like. Each component included in the communication node 200 may be connected by a bus 270 to communicate with each other.

However, each component included in the communication node 200 may be connected through an individual interface or an individual bus centered on the processor 220 instead of the common bus 270 . For example, the processor 220 may be connected to at least one of the memory 220, the transmission/reception device 230, the input interface device 240, the output interface device 250, and the storage device 260 through a dedicated interface. .

The processor 220 may execute a program command stored in at least one of the memory 220 and the storage device 260 . The processor 220 may mean a central processing unit (CPU), a graphics processing unit (GPU), or a dedicated processor on which methods according to embodiments of the present disclosure are performed. Each of the memory 220 and the storage device 260 may include at least one of a volatile storage medium and a non-volatile storage medium. For example, the memory 220 may include at least one of a read only memory (ROM) and a random access memory (RAM).

Referring back to FIG. 1, the communication system 100 includes a plurality of base stations (110-1, 110-2, 110-3, 120-1, 120-2), a plurality of terminals 130- 1, 130-2, 130-3, 130-4, 130-5, 130-6). Base stations 110-1, 110-2, 110-3, 120-1, and 120-2 and terminals 130-1, 130-2, 130-3, 130-4, 130-5, and 130-6 The inclusive communication system 100 may be referred to as an “access network”. Each of the first base station 110-1, the second base station 110-2, and the third base station 110-3 may form a macro cell. Each of the fourth base station 120-1 and the fifth base station 120-2 may form a small cell. The fourth base station 120-1, the third terminal 130-3, and the fourth terminal 130-4 may belong to the cell coverage of the first base station 110-1. The second terminal 130-2, the fourth terminal 130-4, and the fifth terminal 130-5 may belong to the cell coverage of the second base station 110-2. The fifth base station 120-2, the fourth terminal 130-4, the fifth terminal 130-5, and the sixth terminal 130-6 may belong to the cell coverage of the third base station 110-3. there is. The first terminal 130-1 may belong to the cell coverage of the fourth base station 120-1. The sixth terminal 130-6 may belong to the cell coverage of the fifth base station 120-2.

Here, each of the plurality of base stations 110-1, 110-2, 110-3, 120-1, and 120-2 is a NodeB, an evolved NodeB, a base transceiver station (BTS), Radio base station, radio transceiver, access point, access node, RSU (road side unit), RRH (radio remote head), TP (transmission point), TRP ( transmission and reception point), eNB, gNB, etc.

Each of the plurality of terminals 130-1, 130-2, 130-3, 130-4, 130-5, and 130-6 is a UE (user equipment), terminal, access terminal, mobile Mobile terminal, station, subscriber station, mobile station, portable subscriber station, node, device, IoT (Internet of Thing) It may be referred to as a device, a mounted device (mounted module/device/terminal or on board device/terminal, etc.), and the like.

Meanwhile, each of the plurality of base stations 110-1, 110-2, 110-3, 120-1, and 120-2 may operate in different frequency bands or may operate in the same frequency band. Each of the plurality of base stations 110-1, 110-2, 110-3, 120-1, and 120-2 may be connected to each other through an ideal backhaul link or a non-ideal backhaul link, and , information can be exchanged with each other through an ideal backhaul link or a non-ideal backhaul link. Each of the plurality of base stations 110-1, 110-2, 110-3, 120-1, and 120-2 may be connected to the core network through an ideal backhaul link or a non-ideal backhaul link. Each of the plurality of base stations 110-1, 110-2, 110-3, 120-1, and 120-2 transmits a signal received from the core network to a corresponding terminal 130-1, 130-2, 130-3, and 130 -4, 130-5, 130-6), and signals received from corresponding terminals 130-1, 130-2, 130-3, 130-4, 130-5, 130-6 are transmitted to the core network can be sent to

In addition, each of the plurality of base stations 110-1, 110-2, 110-3, 120-1, and 120-2 transmits MIMO (eg, single user (SU)-MIMO, multi-user (MU)- MIMO, massive MIMO, etc.), CoMP (coordinated multipoint) transmission, CA (carrier aggregation) transmission, transmission in an unlicensed band, device to device communication (D2D) (or ProSe ( proximity services)) may be supported. Here, each of the plurality of terminals 130-1, 130-2, 130-3, 130-4, 130-5, and 130-6 is a base station 110-1, 110-2, 110-3, 120-1 , 120-2) and operations supported by the base stations 110-1, 110-2, 110-3, 120-1, and 120-2 may be performed. For example, the second base station 110-2 can transmit a signal to the fourth terminal 130-4 based on the SU-MIMO scheme, and the fourth terminal 130-4 uses the SU-MIMO scheme. A signal may be received from the second base station 110-2. Alternatively, the second base station 110-2 may transmit a signal to the fourth terminal 130-4 and the fifth terminal 130-5 based on the MU-MIMO scheme, and the fourth terminal 130-4 And each of the fifth terminal 130-5 may receive a signal from the second base station 110-2 by the MU-MIMO method.

Each of the first base station 110-1, the second base station 110-2, and the third base station 110-3 may transmit a signal to the fourth terminal 130-4 based on the CoMP scheme, and The terminal 130-4 may receive signals from the first base station 110-1, the second base station 110-2, and the third base station 110-3 by CoMP. Each of the plurality of base stations 110-1, 110-2, 110-3, 120-1, and 120-2 includes a terminal 130-1, 130-2, 130-3, and 130-4 belonging to its own cell coverage. , 130-5, 130-6) and a CA method. Each of the first base station 110-1, the second base station 110-2, and the third base station 110-3 controls D2D between the fourth terminal 130-4 and the fifth terminal 130-5. and each of the fourth terminal 130-4 and the fifth terminal 130-5 may perform D2D under the control of the second base station 110-2 and the third base station 110-3, respectively. .

Next, methods for transmitting and receiving radio signals in a communication system will be described. Here, even when a method performed in a first communication node among communication nodes (for example, transmission or reception of a signal) is described, the second communication node corresponding thereto is a method performed in the first communication node and a method corresponding thereto. (eg, receiving or transmitting a signal). For example, when an operation of a receiving node is described, a corresponding transmitting node may perform an operation corresponding to that of the receiving node. Conversely, when the operation of the transmitting node is described, the corresponding receiving node may perform an operation corresponding to that of the transmitting node.

3 is a conceptual diagram illustrating an embodiment of a structure of a radio frame in a communication system.

Referring to FIG. 3, in a communication system, one radio frame may consist of 10 subframes, and one subframe may consist of 2 time slots. One time slot may have a plurality of symbols in the time domain and may include a plurality of subcarriers in the frequency domain. A plurality of symbols in the time domain may be OFDM symbols. For convenience, an embodiment of a radio frame structure in a communication system will be described below using an OFDM transmission mode in which a plurality of symbols in the time domain are OFDM symbols as an example. However, this is only an example for convenience of explanation, and an embodiment of a radio frame structure in a communication system is not limited thereto. For example, different embodiments of a radio frame structure in a communication system may be configured to support other transmission modes, such as a single carrier (SC) transmission mode.

In one embodiment of the communication system, one or more of the numerologies of Table 1 are used for various purposes such as inter-carrier interference (ICI) reduction according to frequency band characteristics and latency reduction according to service characteristics. this can be used

Table 1 is only an example for convenience of description, and embodiments of numerologies used in the communication system may not be limited thereto. Each numerology μ may correspond to information of a subcarrier spacing (SCS) Δf and a cyclic prefix (CP). The terminal determines the values of the numerology μ and CP applied to the downlink bandwidth part or the uplink bandwidth part based on the upper layer parameters such as 'subcarrierSpacing' and 'cyclicPrefix'. You can check.

) 서브프레임(subframe)(320)으로 구성되는 프레임(frame)(330), 하나 이상의 (

) 슬롯(slot)(310)으로 구성되는 서브프레임(320), 그리고

개의 OFDM 심볼(symbol)들로 구성되는 슬롯(310)으로 표현될 수 있다. 이때 각 변수

,

,

의 값들은 설정된 뉴머롤러지에 따라 정규 사이클릭 프리픽스인 경우는 표 2의 값을 따를 수 있고, 확장 사이클릭 프리픽스인 경우는 표 3의 값을 따를 수 있다. 한 슬롯에 포함되는 OFDM 심볼들은 상위 계층 시그날링 혹은 상위 계층 시그날링 및 L1 시그날링의 조합에 의하여 '하향링크(downlink)', '플렉서블(flexible)' 또는 '상향링크(uplink)'로 구별될 수 있다.Time resources for transmitting radio signals in the communication system 300 include one or more (

) A frame 330 composed of subframes 320, one or more (

) a subframe 320 composed of slots 310, and

It can be represented as a slot 310 consisting of OFDM symbols. At this time, each variable

,

,

The values of may follow the values of Table 2 in the case of a regular cyclic prefix according to the set numerology, and may follow the values of Table 3 in the case of an extended cyclic prefix. OFDM symbols included in one slot can be distinguished as 'downlink', 'flexible' or 'uplink' by higher layer signaling or a combination of higher layer signaling and L1 signaling. can

In one embodiment of the communication system, the frame 330 may have a length of 10ms, and the subframe 320 may have a length of 1ms. Each frame 330 may be divided into two half-frames having the same length, and the first half-frame (half-frame 0) is composed of subframes 320 numbered 0 to 4. The second half frame (half-frame 1) may be composed of subframes 5 to 9 (320). One carrier may include a set of frames for uplink (uplink frames) and a set of frames for downlink (downlink frames).

)을 가질 수 있다.One slot may have 6 (in case of extended cyclic prefix) or 7 (in case of normal cyclic prefix) OFDM symbols. A time-frequency domain defined as one slot may be referred to as a resource block (RB). If one slot has 7 OFDM symbols, one subframe has 14 OFDM symbols (

) can have.

A subframe may be divided into a control area and a data area. A physical downlink control channel (PDCCH) may be allocated to the control region. A physical downlink shared channel (PDSCH) may be allocated to the data area. Some of the subframes may be special subframes. The special subframe may include a downlink pilot time slot (DwPTS), a guard period (GP), and an uplink pilot time slot (UpPTS). DwPTS can be used for time and frequency synchronization estimation and cell search of a UE. The GP can be regarded as a section for removing interference caused by multipath delay of a downlink signal.

In one embodiment of the communication system, in order to access a wireless network, a user may perform serving cell identification after acquiring time/frequency synchronization with the network. The serving cell identification may be performed, for example, through physical cell identity (PCI) estimation using a predetermined synchronization signal. Each cell may have a different PCI and may transmit a synchronization signal including information for identifying the PCI (ie, a synchronization signal indicating the PCI). For an easy cell identification operation, cross-correlation characteristics between synchronization signals indicating different PCIs may be excellent, and variability of cross-correlation characteristics of all possible synchronization signal pairs may be low.

Meanwhile, the number of distinguishable PCIs may be limited according to a synchronization signal design method. In order to overcome this limitation and increase the number of distinguishable PCIs, in one embodiment of the communication system, cyclically distinct sequences are cyclically shifted to obtain linearly distinct synchronization. A method of generating a signal may be used. Sequences generated through circular movement in this way may not follow the cross-correlation characteristics of the original sequences. As a result, cross-correlation characteristics between the generated synchronization signal pairs may be deteriorated, and variability of the cross-correlation characteristics may increase. A technique capable of effectively increasing the number of discriminable PCIs while maintaining cross-correlation characteristics of synchronization signals and their variability may be required.

In one embodiment of the communication system, the synchronization signal may be constructed based on one or more sequences. One or more sequences constituting the synchronization signal may be arranged in a frame 330, a subframe 320, a slot 310, or an OFDM symbol constituting the slot 310 in the time domain. Meanwhile, one or more sequences constituting the synchronization signal may be modulated and mapped to a plurality of subcarriers in the frequency domain. In one embodiment of the communication system, one or more sequences constituting a synchronization signal may correspond to one or more binary sequences or complex sequences.

4 is a flowchart for explaining a first embodiment of a method for transmitting and receiving signals in a communication system.

Referring to FIG. 4 , a communication system 400 may include a plurality of communication nodes. For example, the communication system 400 may include at least a first communication node 401 and a second communication node 402 . The first communication node 401 may be the same as or similar to the cell that transmits the synchronization signal described with reference to FIG. 3 . The second communication node 402 may be the same as or similar to the receiving node for receiving the synchronization signal described with reference to FIG. 3 . Hereinafter, in describing an embodiment of a method for transmitting and receiving a signal in a communication system with reference to FIG. 4, descriptions overlapping those described with reference to FIGS. 1 to 3 may be omitted.

In one embodiment of the communication system 400, the first communication node 401 may correspond to a cell, a base station, a network, or the like. The first communication node 401 may transmit a first signal including identification information to be used by users (UE, terminals, etc.) within the coverage of the first communication node 401 to identify the first communication node 401. there is. For example, the first communication node 401 may be identified by first identification information. The first identification information may correspond to physical cell identity (PCI). Alternatively, the first identification information may correspond to information about PCI. The first identification information may be generated based on PCI. The first signal including the first identification information may correspond to a synchronization signal. The first signal may correspond to a secondary synchronization signal (SSS). However, this is only an example for convenience of explanation, and the first embodiment of the signal transmission/reception method in the communication system 400 is not limited thereto. The first signal may be composed of one or more sequences (hereinafter, one or more first signal sequences). The second communication node 402 may receive the first signal transmitted from the first communication node 401 . The second communication node 402 may perform identification of the first communication node 401 based on the received first signal.

Specifically, the first communication node 401 may generate one or more binary sequences (S410). One or more binary sequences may correspond to a PN sequence. A PN sequence may be referred to as an 'm-sequence'. The first communication node 401 may generate one or more first signal sequences based on one or more binary sequences (S420).

The first communication node 401 may modulate one or more first signal sequences generated in step S420 and allocate (or map) them to radio resources (S430). For example, the first communication node 401 may modulate one or more generated first signal sequences to generate one or more modulation symbols. The first communication node 401 may allocate the generated one or more modulation symbols onto a time resource and/or a frequency resource.

The first communication node 401 may transmit a first signal composed of one or more first signal sequences modulated and mapped to radio resources to the second communication node 402 (S440). In other words, the first communication node 401 may transmit to the second communication node 402 a first signal consisting of one or more modulation symbols in which one or more first signal sequences are modulated.

The second communication node 402 may receive the first signal transmitted from the first communication node 401 (S440). The second communication node may perform an identification operation for the first communication node 401 based on the first signal received in step S440 (S450). Identification in step S450 may include, for example, cell identification.

5A and 5B are conceptual diagrams for explaining a first embodiment of a radio signal structure in a communication system.

Referring to FIGS. 5A and 5B , a communication system may include a plurality of communication nodes. The communication system may be the same as or similar to the communication system 400 described with reference to FIG. 4 . Hereinafter, in describing the first embodiment of a radio signal structure in a communication system with reference to FIGS. 5A and 5B , descriptions overlapping those described with reference to FIGS. 1 to 4 may be omitted.

The first communication node may generate and transmit a radio signal to the second communication node. A first communication node may generate one or more radio signals. The first communication node may generate one or more radio signal sequences to generate one or more radio signals. The first communication node may modulate one or more elements constituting one or more generated radio signal sequences and map them to one or more subcarriers in the frequency domain.

In one embodiment of the communication system, when the number of one or more subcarriers to which one or more radio signal sequences are mapped is a natural number N of 1 or more, the index k of the subcarriers may have a natural number value greater than or equal to 0 and less than or equal to N-1. That is, k = 0, 1, ..., may be N-1. One or more radio signal sequences may be generated based on a predetermined identification index v. Here, the identification index v may correspond to, for example, the first identification information described with reference to FIG. 4 . The identification index v may correspond to first identification information. The identification index v may be determined based on the first identification information. Alternatively, the first identification information may be determined based on the identification index v. One or more radio signal sequences may be expressed as S _v (k), for example. Alternatively, one or more radio signal sequences may be distinguished according to a generation method and expressed as S _v,1 (k), S _v,2 (k), S _v,3 (k), S _v,4 (k), etc. there is.

In one embodiment of the communication system, the first radio signal may correspond to the first signal described with reference to FIG. 4 . The first radio signal may correspond to a synchronization signal, SSS, and the like. Alternatively, the first radio signal may correspond to a signal newly defined for cell identification. The first signal may also be referred to as an 'identification signal'.

In one embodiment of the communication system, the radio signal sequence S _v (k) may be generated based on two binary sequences. The radio signal sequence S _v (k) may be composed of N elements (S _v (0), S _v (1), ..., S _v (N-1)). A radio signal sequence S _v (k) may be modulated and mapped to N subcarriers. 5A and 5B show a case in which N is greater than 1 (ie, a case in which a radio signal sequence S _v (k) is modulated and mapped to a plurality of subcarriers). However, this is only an example for convenience of description, and the first embodiment of the radio signal structure in the communication system is not limited thereto.

Referring to FIG. 5A, in the first radio signal structure 500, a radio signal sequence S _v (k) is modulated to generate N subcarriers represented by index k (k = 0, 1, ..., N-1). can be mapped to Each of the N elements (S _{v (} 0), S _v (1), ..., S _v (N-1)) constituting the radio signal sequence S v (k) is a subcarrier having a corresponding index. can be mapped to Here, N subcarriers to which the radio signal sequence S _v (k) is mapped (ie, N subcarriers to which modulation symbols obtained by modulating the radio signal sequence S _v (k) are mapped) may be included in the first subcarrier group. . The N subcarriers constituting the first subcarrier group may be adjacent to or spaced apart from each other in the frequency domain. 5A shows a case in which at least some of the N subcarriers constituting the first subcarrier group are arranged adjacent to each other, but this is only an example for convenience of description and the first embodiment of the radio signal structure in the communication system Not limited to this. For example, the first subcarrier group may be composed of N subcarriers spaced apart from each other. In other words, the first subcarrier group may be composed of N subcarriers that are not adjacent to each other.

One or more null subcarriers may be disposed around or between the N subcarriers constituting the first subcarrier group. A signal may not be loaded on the null subcarrier. In other words, modulation symbols may not be allocated to null subcarriers. A null subcarrier may have a value of 0. The null subcarrier may correspond to a gap subcarrier, a direct current (DC) subcarrier, or the like. Null subcarriers can be placed to easily identify each subcarrier.

Null subcarriers may be disposed at the front end and/or the rear end of the first subcarrier group in the frequency domain. For example, null subcarriers may be disposed at the front end of the subcarrier corresponding to subcarrier index 0 and/or at the rear end of the subcarrier corresponding to subcarrier index N-1. Also, one or more null subcarriers may be disposed between the N subcarriers constituting the first subcarrier group. For example, null subcarriers may be disposed in front and/or after one or more central subcarriers (hereinafter referred to as center subcarriers) among the N subcarriers constituting the first subcarrier group. Alternatively, the first subcarrier group may be divided into a plurality of subgroups each including one or more subcarriers. Null subcarriers may be arranged at the front and/or the rear of each subgroup.

Referring to FIG. 5B, in the second radio signal structure 550, a radio signal sequence S _v (k) is modulated to generate N subcarriers represented by index k (k = 0, 1, ..., N-1). can be mapped to Here, N subcarriers to which the radio signal sequence S _v (k) is mapped may be included in the second subcarrier group. The second subcarrier group may include N subcarriers, at least some of which are adjacent to each other in the frequency domain. Here, null subcarriers may not be disposed between the N subcarriers constituting the second subcarrier group.

6A to 6D are conceptual diagrams for explaining first and second embodiments of a method for generating a radio signal in a communication system.

Referring to FIGS. 6A and 6B , a communication system may include a plurality of communication nodes. The communication system may be the same as or similar to the communication system 400 described with reference to FIG. 4 . In a communication system, a radio signal may have a structure identical to or similar to the first radio signal structure 500 described with reference to FIG. 5A or the second radio signal structure 550 described with reference to FIG. 5B. Hereinafter, in describing the first and second embodiments of the radio signal generation method with reference to FIGS. 6A and 6B, overlapping descriptions with those described with reference to FIGS. 1 to 5B may be omitted.

6A is a conceptual diagram for explaining a first embodiment of a radio signal generation method in a communication system.

First Embodiment of Radio Signal Generation Method

In one embodiment of the communication system, the first communication node may generate a radio signal according to the first embodiment of a method for generating a radio signal. The first embodiment of the radio signal generation method may be referred to as a 'Binary Phase Shift Keying (BPSK) method'. The first embodiment of the radio signal generation method may be referred to as 'random BPSK method'.

In a first embodiment of the radio signal generation method, the first radio signal may be generated based on one or more basic radio signal sequences. One or more basic radio signal sequences may be generated based on one or more binary sequences. In other words, one or more basic radio signal sequences may correspond to a result obtained by converting one or more binary sequences according to the first embodiment of the radio signal generation method. For example, one or more binary sequences may correspond to a pseudo-noise (PN) sequence or a binary PN sequence. One or more binary sequences may correspond to an m-sequence. Alternatively, one or more binary sequences may be composed of a gold sequence generated through an element-wise exclusive-OR (XOR) operation on two different PN sequences.

In one embodiment of the communication system, a basic radio signal sequence S _v (k) may be generated based on two first binary sequences x ₀ (i) and x ₁ (i). For example, the basic radio signal sequence S _v (k) may be defined identically or similarly to Equation 1.

는 실수 W보다 작은 가장 높은 정수를 의미할 수 있다. N은 주파수 영역에서 제1 무선 신호가 매핑되는 하나 이상의 부반송파들의 수를 의미할 수 있다. 이를테면, 수학식 1에서 N은 127일 수 있다. 2개의 제1 이진 시퀀스들 x₀(i) 및 x₁(i)는 최대 차수 7을 가지는 서로 다른 생성 다항식들(generator polynomials)에 기초하여 정의될 수 있다. 2개의 제1 이진 시퀀스들 x₀(i) 및 x₁(i) 각각은 점화식 'x₀(i+7)=[x₀(i+4)+x₀(i+0)]₂' 및 'x₁(i+7)=[x₁(i+1)+x₁(i+0)]₂' 에 기초하여 결정될 수 있다. 점화식들 각각의 2-모듈로 연산은 XOR 연산과 동일 또는 유사할 수 있다. 이를테면, 점화식들 각각의 2-모듈로 연산은 선형 피드백 시프트 레지스터(Linear Feedback Shift Register, LFSR)에서의 XOR 연산에 대응될 수 있다. 식별 인덱스 v는 g 및 u를 입력 변수로 하는 함수 'fuc(g,u)=3g+u'에 기초하여 결정될 수 있다. 여기서, g는 셀 그룹 식별자(cell group identity, CGI)에 해당할 수 있고, u는 물리적 식별자(physical identity, PID)에 해당할 수 있다. 수학식 1에 표시된 숫자들은 설명의 편의를 위한 예시일 뿐이며, 무선 신호 생성 방식의 제1 실시예는 이에 국한되지 않는다.In Equation 1, [a] _b may mean a b-modulo operation for a value.

may mean the highest integer smaller than the real number W. N may mean the number of one or more subcarriers to which the first radio signal is mapped in the frequency domain. For example, in Equation 1, N may be 127. The two first binary sequences x ₀ (i) and x ₁ (i) may be defined based on different generator polynomials having a maximum degree of 7. Each of the two first binary sequences x ₀ (i) and x ₁ (i) has the recurrence formula 'x ₀ (i+7)=[x ₀ (i+4)+x ₀ (i+0)] ₂ 'and It may be determined based on 'x ₁ (i+7)=[x ₁ (i+1)+x ₁ (i+0)] ₂ '. The 2-modulo operation of each of the recurrence equations may be the same as or similar to the XOR operation. For example, a 2-modulo operation of each of the recurrence equations may correspond to an XOR operation in a Linear Feedback Shift Register (LFSR). The identification index v may be determined based on a function 'fuc(g,u)=3g+u' having g and u as input variables. Here, g may correspond to a cell group identity (CGI) and u may correspond to a physical identity (PID). The numbers shown in Equation 1 are only examples for convenience of description, and the first embodiment of the wireless signal generation method is not limited thereto.

In Equation 1, Ξ may mean the number of distinguishable identification index v values. That is, the number of values that the identification index v may have may correspond to Ξ=1008. A total of 1008 identification indices can be identified by the basic radio signal sequence S _v (k) generated according to Equation 1. However, this is only an example for convenience of explanation, and the first embodiment of the wireless signal generation method is not limited thereto.

Theoretically, the maximum number of distinguishable identification indices based on the basic radio signal sequence S _v (k) is two first binary sequences constituting the basic radio signal sequence S _v (k) x ₀ (i) and x ₁ It can be defined as a combination of all cyclic shift indices that can be generated in (i). Each of the cyclic shift indices v ₀ and v ₁ associated with the two first binary sequences x ₀ (i) and x ₁ (i) may have a total of 127 values. Therefore, theoretically, the maximum number of identification indices that can be distinguished based on the basic radio signal sequence S _v (k) may correspond to 127 ² =16129. The basic radio signal sequence S _v (k) may have up to 127 cyclically distinguishable sequences.

In one embodiment of the communication system, the value of the identification index v may be selected between 0 and Ξ-1. If v = 19 is selected, it can be calculated as g = 6, g ₀ =0, g ₁ =6, u = 1 based on Equation 1. In this case, cyclic shift indices associated with the two first binary sequences x ₀ (i) and x ₁ (i) may be calculated as v ₀ =5 and v ₁ =6. A basic radio signal sequence S _v (k) may be calculated based on the values of the cyclic movement indices v ₀ and v ₁ calculated in this way.

In Equation 1, the formula for calculating the basic radio signal sequence S _v (k) based on the two binary sequences first binary sequences x ₀ (i) and x ₁ (i) 'S _v (k) = (1 -2(x ₀ ([k+v ₀ ] ₁₂₇ ))(1-2(x ₁ ([k+v ₁ ] ₁₂₇ ))' may correspond to a BPSK operation. The basic radio signal sequence S _v ( k) may have a value of 1 or -1.

6A shows the basic radio signal sequence S _v (k) generated based on Equation 1 in the first embodiment of the radio signal generation method, or the first radio signal generated based on the basic radio signal sequence S _v (k) It can be seen that an embodiment of a constellation (hereinafter referred to as a basic constellation) 610 is shown. The first radio signal may be represented by two constellation points on the basic constellation 610 . Both of the two constellation points corresponding to the first radio signal may have a real value of 1 or -1.

6B to 6D are conceptual diagrams for explaining a second embodiment of a radio signal generation method in a communication system.

Second embodiment of radio signal generation method

In one embodiment of the communication system, the first communication node may generate a radio signal according to the second embodiment of the method for generating a radio signal. The second embodiment of the radio signal generation method may be referred to as a 'Quadrature Phase Shift Keying (QPSK) method'. The second embodiment of the radio signal generation method may be referred to as 'random QPSK method'. The second embodiment of the radio signal generation method may be referred to as 'π/4 QPSK method'.

In a second embodiment of the radio signal generation method, the first radio signal may be generated based on one or more first radio signal sequences. One or more first radio signal sequences may be generated based on one or more binary sequences. One or more first radio signal sequences may be expressed as S _v,1 (k).

In one embodiment of the communication system, the first radio signal sequence S _v,1 (k) may be generated based on the second binary sequence x ₂ (i) and the third binary sequence x ₃ (i). The first radio signal sequence S _v,1 (k) may be generated based on the first intermediate sequence Ψ _v (m), and the first intermediate sequence Ψ _v (m) is a second binary sequence x ₂ (i) and It can be defined based on the third binary sequence x ₃ (i). The second binary sequence x ₂ (i) and the third binary sequence x ₃ (i) may correspond to PN sequences. For example, the first radio signal sequence S _v,1 (k) may be defined identically or similarly to Equation 2.

In Equation 2, the value of N may be 127. The second binary sequence x ₂ (i) and the third binary sequence x ₃ (i) may be defined based on different generator polynomials having a maximum degree of 8. The second binary sequence x ₂ (i) is the second recursive expression 'x ₂ (i+8)=[x ₂ (i+7)+x ₂ (i+6)+x ₂ (i+5)+x ₂ ( i+2)+x ₂ (i+1)+x ₂ (i)] ₂ '. The third binary sequence x ₃ (i) is the third recursive expression 'x ₃ (i+8)=[x ₃ (i+7)+x ₃ (i+6)+x ₃ (i+1)+x ₃ ( i)] ₂ '. The recursive formulas and numbers shown in Equation 2 are only examples for convenience of description, and the second embodiment of the wireless signal generation method is not limited thereto. For example, the second binary sequence x ₂ (i) and the third binary sequence x ₃ (i) may be generated in various ways other than the recursive equations shown in Equation 2.

Theoretically, the maximum number of identification indices that can be distinguished based on the first radio signal sequence S _v,1 (k) is the second binary sequence constituting the first radio signal sequence S _v,1 (k) x ₂ (i) and a combination of all cyclic shift indices that can be generated in the third binary sequence x ₃ (i). Each of the cyclic movement indices v ₂ and v ₃ associated with the second binary sequence x ₂ (i) and the third binary sequence x ₃ (i) may have a total of 255 values. Therefore, theoretically, the maximum number of identification indices that can be distinguished based on the first radio signal sequence S _v,1 (k) may correspond to 255 ² =65025. The first radio signal sequence S _v,1 (k) may have up to 255 cyclically distinct sequences.

, g₁=[333]_Ω, u=0과 같이 계산될 수 있다. 이 경우, 2개의 제1 이진 시퀀스들 x₀(i) 및 x₁(i)와 관련된 순환 이동 인덱스들은 v₂=

및 v₃=[333]_Ω과 같이 계산될 수 있다. 이와 같이 계산된 순환 이동 인덱스들 v₂ 및 v₃의 값에 기초하여 제1 무선 신호 시퀀스 S_v,1(k)가 계산될 수 있다. 여기서, Ω는 Ξ에 기초하여 계산될 수 있다. 이를테면, Ω는 Ξ에 기초하여 수학식 3과 동일 또는 유사하게 계산될 수 있다.In Equation 2, Ξ may mean the number of distinguishable identification index v values. A total of Ξ identification indices can be identified by the first radio signal sequence S _v,1 (k) generated according to Equation 2. In one embodiment of the communication system, the value of the identification index v may be selected between 0 and Ξ-1. If v = 999 is selected, based on Equation 2, g = 333, g ₀ =

, g ₁ =[333] _Ω , u = 0. In this case, the cyclic shift indices associated with the two first binary sequences x ₀ (i) and x ₁ (i) are v ₂ =

and v ₃ =[333] _Ω . A first radio signal sequence S _v,1 (k) may be calculated based on the values of the cyclic movement indices v ₂ and v ₃ calculated as described above. Here, Ω can be calculated based on Ξ. For example, Ω may be calculated identically or similarly to Equation 3 based on Ξ.

는 실수 W보다 큰, 가장 작은 정수를 의미할 수 있다. 만약 Ξ=1008과 같이 설정될 경우, Ω=168로 결정될 수 있다. 이에 따라, v₂=30 및 v₃=165 와 같이 결정될 수 있다. 만약 Ξ의 값이 1008의 2배(즉, 2016)로 설정될 경우, Ω=224로 결정될 수 있다. 이에 따라, v₂=30 및 v₃=109 와 같이 결정될 수 있다. 이에 따라, v₂=30 및 v₃=109 와 같이 결정될 수 있다.In Equation 3,

may mean the smallest integer larger than the real number W. If Ξ = 1008, it can be determined as Ω = 168. Accordingly, v ₂ =30 and v ₃ =165 may be determined. If the value of Ξ is set to twice 1008 (ie, 2016), Ω=224 may be determined. Accordingly, v ₂ =30 and v ₃ =109 may be determined. Accordingly, v ₂ =30 and v ₃ =109 may be determined.

In Equation 2, a formula for calculating the first intermediate sequence Ψ v (m) based on the second binary sequence x ₂ (i) and the third binary sequence x ₃ (i) ' _{Ψ v (} m) = 1-2 [ x ₂ ([m+v ₂ ] ₂₅₅ ))+x ₃ ([m+v ₃ ] ₂₅₅ )] ₂ ′ may correspond to a BPSK operation. The first intermediate sequence Ψ _v (m) may have a value of 1 or -1.

On one side of FIG. 6B, an embodiment of a constellation for a first intermediate sequence Ψ _v (m) generated based on Equation 2 in a second embodiment of a radio signal generation method (hereinafter, a first intermediate constellation) ( 620) can be seen as shown. The first intermediate constellation 620 may be the same as or similar to the basic constellation 610 described with reference to FIG. 6A .

은, QPSK 연산에 대응될 수 있다. 제1 무선 신호 시퀀스 S_v,1(k)는 제1 중간 시퀀스 Ψ_v(m)를 구성하는 서로 2개의 인접한 엘리먼트들에 대한 연산을 통하여 정의될 수 있다. 제1 중간 시퀀스 Ψ_v(m)를 구성하는 서로 2개의 인접한 엘리먼트들은 실수부 및 허수부로 변환될 수 있다. 이를테면, 제1 중간 시퀀스 Ψ_v(m)를 구성하는 서로 2개의 인접한 엘리먼트들 중 짝수 인덱스를 가지는 엘리먼트 Ψ_v(2k)(이하, 짝수 번째 엘리먼트)는 실수부로 변환될 수 있고, 홀수 인덱스를 가지는 엘리먼트 Ψ_v(2k+1)(이하, 홀수 번째 엘리먼트)는 허수부로 변조될 수 있다. 제1 중간 시퀀스 Ψ_v(m)의 짝수 번째 엘리먼트 Ψ_v(2k)는

가 곱해져서, 제1 무선 신호 시퀀스 S_v,1(k)의 실수부로 변환될 수 있다. 제1 중간 시퀀스 Ψ_v(m)의 홀수 번째 엘리먼트 Ψ_v(2k+1)는

가 곱해져서, 제1 무선 신호 시퀀스 S_v,1(k)의 허수부로 변환될 수 있다. 이와 같이 생성된 제1 무선 신호 시퀀스 S_v,1(k)는 복소 시퀀스에 해당할 수 있다. 이를테면, 엘리먼트 Ψ_v(2k) 및 엘리먼트 Ψ_v(2k+1)의 값에 따라서, 제1 무선 신호 시퀀스 S_v,1(k)는

,

,

,

등의 값을 가질 수 있다.Calculation formula for calculating the first radio signal sequence S _v,1 (k) based on the first intermediate sequence Ψ _v (m) calculated based on the BPSK operation in Equation 2

may correspond to QPSK operation. The first radio signal sequence S _v,1 (k) may be defined through an operation on two adjacent elements constituting the first intermediate sequence Ψ _v (m). Two adjacent elements constituting the first intermediate sequence Ψ _v (m) may be converted into a real part and an imaginary part. For example, an element Ψ _v (2k) (hereinafter, an even-numbered element) having an even index among two adjacent elements constituting the first intermediate sequence Ψ _v (m) may be converted into a real part, and having an odd index The element Ψ _v (2k+1) (hereinafter, an odd-numbered element) may be modulated with an imaginary part. The even-numbered element Ψ _v (2k) of the first intermediate sequence Ψ _v (m) is

may be multiplied and converted into the real part of the first radio signal sequence S _v,1 (k). The odd-numbered element Ψ _v (2k+1) of the first intermediate sequence Ψ _v (m) is

may be multiplied and converted into an imaginary part of the first radio signal sequence S _v,1 (k). The first radio signal sequence S _v,1 (k) generated in this way may correspond to a complex sequence. For example, according to the values of element Ψ _v (2k) and element Ψ _v (2k + 1), the first radio signal sequence S _v,1 (k) is

,

,

,

can have values such as

On the other side of FIG. 6B, the first radio signal sequence S _v,1 (k) generated based on Equation 2 in the second embodiment of the radio signal generation method or the first radio signal sequence S _v,1 (k) It can be seen that an embodiment (hereinafter referred to as a first final constellation) 630 of a constellation of a first radio signal generated based thereon is shown. The first radio signal may be represented by four constellation points on the first final constellation 630 . All four constellation points corresponding to the first radio signal may have complex coordinates having a real part and an imaginary part on a complex plane.

일 수 있다. 성상점 01에 대응되는 제1 무선 신호 시퀀스 S_v,1(k)의 값은

일 수 있다. 성상점 10에 대응되는 제1 무선 신호 시퀀스 S_v,1(k)의 값은

일 수 있다. 성상점 11에 대응되는 제1 무선 신호 시퀀스 S_v,1(k)의 값은

일 수 있다.In the second final constellation map 640 shown in FIG. 6C, the first radio signal sequence S _{v,1 (k) and the first radio signal sequence S v,1} (k) to which each of the four constellation points displayed on the first final constellation map 630 corresponds. It can be seen that the relationship between the values of the intermediate sequence Ψ _v (m) is shown. In the second final constellation 640, the constellation point '00' may correspond to a case where Ψ _v (2k) = 1 and Ψ _v (2k + 1) = 1. Constellation point '01' may correspond to the case where Ψ _v (2k) = 1 and Ψ _v (2k + 1) = -1. Constellation point '10' may correspond to a case where Ψ _v (2k) = -1 and Ψ _v (2k + 1) = 1. Constellation point '11' may correspond to cases where Ψ _v (2k) = -1 and Ψ _v (2k + 1) = -1. On the second final constellation 640, the value of the first radio signal sequence S _v,1 (k) corresponding to constellation point 00 is

can be The value of the first radio signal sequence S _v,1 (k) corresponding to constellation point 01 is

can be The value of the first radio signal sequence S _v,1 (k) corresponding to constellation point 10 is

can be The value of the first radio signal sequence S _v,1 (k) corresponding to constellation point 11 is

can be

와 같이 변경될 수도 있다. 이 경우, 수학식 2는 수학식 4와 같이 변경될 수 있다.On the other hand, the formula for calculating the first radio signal sequence S _v,1 (k) based on the first intermediate sequence Ψ _v (m) in Equation 2 is

may be changed as In this case, Equation 2 may be changed to Equation 4.

일 수 있다. 성상점 01에 대응되는 제1 무선 신호 시퀀스 S_v,1(k)의 값은

일 수 있다. 성상점 10에 대응되는 제1 무선 신호 시퀀스 S_v,1(k)의 값은

일 수 있다. 성상점 11에 대응되는 제1 무선 신호 시퀀스 S_v,1(k)의 값은

일 수 있다.6D shows the first radio signal sequence S _v,1 (k) generated based on the modified Equation 4 or the first radio signal generated based on the first radio signal sequence S _v,1 (k). It can be seen that an embodiment of a constellation (hereinafter referred to as a third final constellation) 650 is shown. In the third final constellation 650, the value of the first radio signal sequence S _v,1 (k) corresponding to constellation point 00 is

can be The value of the first radio signal sequence S _v,1 (k) corresponding to constellation point 01 is

can be The value of the first radio signal sequence S _v,1 (k) corresponding to constellation point 10 is

can be The value of the first radio signal sequence S _v,1 (k) corresponding to constellation point 11 is

can be

The basic radio signal sequence S _v (k) generated based on Equation 1 and the first generated radio signal sequence S _v,1 (k) generated based on Equation 2 or Equation 4 are the same as in Table 4 or can be similarly compared.

Referring to Table 4, the number N of subcarriers to which the basic radio signal sequence S _v (k) and the first radio signal sequence S _v,1 (k) are modulated and mapped may be 127. However, the maximum number of cyclically distinguishable sequences, 16129 and 65025, may differ by about 4 times. That is, the first radio signal generated based on the first radio signal sequence S _v,1 (k) uses the same amount of frequency resources as the first radio signal generated based on the basic radio signal sequence S _v (k). However, it can have the advantage of supporting 4 times more identification indexes. In addition, since the first radio signal sequence S _v,1 (k) is generated based on cyclically distinguishable sequences, the synchronization signal pairs generated based on the first radio signal sequence S _v,1 (k) The cross-correlation properties and their variability can be maintained. In other words, the first radio signal sequence S _v,1 (k) may have excellent cross-correlation characteristics while having the advantages shown in Table 4 compared to the basic radio signal sequence S _v (k), and the cross-correlation Characteristic variability may be low. In addition, the first radio signal generated based on the first radio signal sequence S _v,1 (k) may have an advantage of being robust against an integer multiple of a carrier frequency offset (CFO).

7A to 7H are conceptual diagrams for explaining a third embodiment of a radio signal generation method in a communication system.

Referring to FIGS. 7A to 7H , a communication system may include a plurality of communication nodes. The communication system may be the same as or similar to the communication system 400 described with reference to FIG. 4 . In the communication system, the second radio signal may have the same or similar structure as the first radio signal structure 500 described with reference to FIG. 5A or the second radio signal structure 550 described with reference to FIG. 5B. Hereinafter, in describing the third embodiment of the radio signal generation method with reference to FIGS. 7A to 7B , overlapping content with that described with reference to FIGS. 1 to 6B may be omitted.

Third embodiment of radio signal generation method

In one embodiment of the communication system, the first communication node may generate the second radio signal according to the third embodiment of the radio signal generation method. In a third embodiment of the radio signal generation method, the second radio signal may be generated based on one or more second radio signal sequences. One or more second radio signal sequences may be generated based on one or more binary sequences. One or more second radio signal sequences may be expressed as S _v,2 (k).

In one embodiment of the communication system, the second radio signal sequence S _v,2 (k) may be generated based on the second binary sequence x ₂ (i) and the third binary sequence x ₃ (i). The second radio signal sequence S _v,2 (k) may be generated based on the first intermediate sequence Ψ _v (m), and the first intermediate sequence Ψ _v (m) is a second binary sequence x ₂ (i) and It can be defined based on the third binary sequence x ₃ (i). The second binary sequence x ₂ (i) and the third binary sequence x ₃ (i) may correspond to PN sequences. For example, the second radio signal sequence S _v,2 (k) may be defined identically or similarly to Equation 5.

은, 수학식 2에서 제1 무선 신호 시퀀스 S_v,1(k)를 계산하는 계산식

에

또는

가 곱해진 것으로 볼 수 있다. 즉, 수학식 5에 따른 제2 무선 신호 시퀀스 S_v,2(k)는, 수학식 2에 따른 제1 무선 신호 시퀀스 S_v,1(k)에 대하여, 복소 평면 상에서 π/4 크기 또는 -π/4 크기의 회전 변환 연산을 수행한 결과에 해당할 수 있다.Equation 5 may be partly the same as and partly different from Equation 2 described with reference to the second embodiment of the radio signal generation method. A formula for calculating the second radio signal sequence S _v,2 (k) based on the first intermediate sequence Ψ _v (m) in Equation 5

Is, a calculation formula for calculating the first radio signal sequence S _v,1 (k) in Equation 2

to

or

can be seen as multiplied by That is, the second radio signal sequence S _v,2 (k) according to Equation 5 has a size of π / 4 or - on the complex plane with respect to the first radio signal sequence S _v,1 (k) according to Equation 2 This may correspond to a result of performing a π/4 size rotation conversion operation.

7A and 7B show a second radio signal sequence S _v,2 (k) or a second radio signal sequence S _v,2 (k) generated based on Equation 5 in the third embodiment of the radio signal generation method. Embodiments of constellations for the second wireless signal generated based on (hereinafter, a first constellation 710 and a second constellation 720 can be seen as shown.

인 경우에 대응될 수 있다. 제2 무선 신호는 제1 성상도(710) 상에서 4개의 성상점들로 표현될 수 있다. 제1 성상도(710) 상에서 제2 무선 신호에 대응되는 4개의 성상점들은, 모두 복소 평면 상에서 실수값만을 가지거나 허수값만을 가지는 좌표를 가질 수 있다. 다르게 표현하면, 제1 성상도(710) 상에서 제2 무선 신호에 대응되는 4개의 성상점들은, 모두 복소 평면 상에서 실수축 상에 위치하거나 또는 허수축 상에 위치할 수 있다. 제1 성상도(710) 상에서, 성상점 00에 대응되는 제2 무선 신호 시퀀스 S_v,2(k)의 값은 허수 j일 수 있다. 성상점 01에 대응되는 제2 무선 신호 시퀀스 S_v,2(k)의 값은 실수 1일 수 있다. 성상점 10에 대응되는 제2 무선 신호 시퀀스 S_v,2(k)의 값은 실수 -1일 수 있다. 성상점 11에 대응되는 제2 무선 신호 시퀀스 S_v,2(k)의 값은 허수 -j일 수 있다.The first constellation map 710 is

may correspond to the case of The second radio signal may be represented by four constellation points on the first constellation 710 . All four constellation points corresponding to the second radio signal on the first constellation 710 may have coordinates having only real values or only imaginary values on the complex plane. In other words, all four constellation points corresponding to the second radio signal on the first constellation 710 may be located on the real axis or the imaginary axis on the complex plane. On the first constellation 710, the value of the second radio signal sequence S _v,2 (k) corresponding to constellation point 00 may be an imaginary number j. A value of the second radio signal sequence S _v,2 (k) corresponding to the constellation point 01 may be a real number 1. The value of the second radio signal sequence S _v,2 (k) corresponding to constellation point 10 may be -1, a real number. A value of the second radio signal sequence S _v,2 (k) corresponding to constellation point 11 may be an imaginary number -j.

The second radio signal sequence S _v,2 (k) represented by four constellation points on the first constellation 710 shown in FIG. 7A is the first radio signal sequence S _v,1 defined as Equation 2. For (k), it may correspond to a result of performing a π/4 size rotation transformation operation on a complex plane. In other words, the four constellation points on the first constellation 710 are the result of shifting the four constellation points on the second final constellation 640 shown in FIG. 6D by a rotation angle of π/4 on the complex plane. may correspond to

인 경우에 대응될 수 있다. 제2 무선 신호는 제2 성상도(720) 상에서 4개의 성상점들로 표현될 수 있다. 제2 성상도(720) 상에서 제2 무선 신호에 대응되는 4개의 성상점들은, 모두 복소 평면 상에서 실수값만을 가지거나 허수값만을 가지는 좌표를 가질 수 있다. 제2 성상도(720) 상에서, 성상점 00에 대응되는 제2 무선 신호 시퀀스 S_v,2(k)의 값은 실수 1일 수 있다. 성상점 01에 대응되는 제2 무선 신호 시퀀스 S_v,2(k)의 값은 허수 -j일 수 있다. 성상점 10에 대응되는 제2 무선 신호 시퀀스 S_v,2(k)의 값은 허수 j일 수 있다. 성상점 11에 대응되는 제2 무선 신호 시퀀스 S_v,2(k)의 값은 실수 -1일 수 있다.Meanwhile, the second constellation 720

may correspond to the case of The second radio signal may be represented by four constellation points on the second constellation 720 . All four constellation points corresponding to the second radio signal on the second constellation 720 may have coordinates having only real values or only imaginary values on the complex plane. On the second constellation 720, the value of the second radio signal sequence S _v,2 (k) corresponding to constellation point 00 may be a real number 1. The value of the second radio signal sequence S _v,2 (k) corresponding to the constellation point 01 may be an imaginary number -j. A value of the second radio signal sequence S _v,2 (k) corresponding to constellation point 10 may be an imaginary number j. The value of the second radio signal sequence S _v,2 (k) corresponding to constellation point 11 may be -1, a real number.

The second radio signal sequence S _v,2 (k) represented by four constellation points on the second constellation 720 shown in FIG. 7B is the first radio signal sequence S _v,1 defined as Equation 2. For (k), it may correspond to a result of performing a rotation conversion operation of -π/4 size on a complex plane. In other words, the four constellation points on the second constellation 720 are obtained by shifting the four constellation points on the second final constellation 640 shown in FIG. 6D by a rotation angle -π/4 on the complex plane. result may apply.

The second radio signal sequence S _v,2 (k) described with reference to FIGS. 7A and 7B is only an example for convenience of description, and the second embodiment of the radio signal generation method is not limited thereto. For example, in one embodiment of the communication system, the definition of the second radio signal sequence S _v,2 (k) as in Equation 5 may be changed as in Equation 6.

은, 수학식 4에서 제1 무선 신호 시퀀스 S_v,1(k)를 계산하는 계산식

에

또는

가 곱해진 것으로 볼 수 있다. 즉, 수학식 6에 따른 제2 무선 신호 시퀀스 S_v,2(k)는, 수학식 4에 따른 제1 무선 신호 시퀀스 S_v,1(k)에 대하여, 복소 평면 상에서 π/4 크기 또는 -π/4 크기의 회전 변환 연산을 수행한 결과에 해당할 수 있다. 한편, 수학식 5 또는 수학식 6에서 회전변환 연산을 위해 곱해지는

는

로 대체될 수도 있다. 이 경우, 수학식 2 또는 수학식 4에 따른 제1 무선 신호 시퀀스 S_v,1(k)에 대하여, 복소 평면 상에서 3π/4 크기 또는 -3π/4 크기의 회전 변환이 수행되는 것으로 볼 수 있다.A formula for calculating the second radio signal sequence S _v,2 (k) based on the first intermediate sequence Ψ _v (m) in Equation 6

Is, a calculation formula for calculating the first radio signal sequence S _v,1 (k) in Equation 4

to

or

can be seen as multiplied by That is, the second radio signal sequence S _v,2 (k) according to Equation 6 has a size of π / 4 or - on the complex plane with respect to the first radio signal sequence S _v,1 (k) according to Equation 4 This may correspond to a result of performing a π/4 size rotation conversion operation. On the other hand, in Equation 5 or Equation 6, multiplied for rotation conversion operation

Is

may be replaced with In this case, with respect to the first radio signal sequence S _v,1 (k) according to Equation 2 or Equation 4, it can be seen that a rotation transformation of a size of 3π / 4 or a size of -3π / 4 is performed on the complex plane. .

It can be seen that FIG. 7C shows a second radio signal sequence S _v,2 (k) or a third embodiment (hereinafter referred to as a third constellation) 730 of a constellation for the second radio signal. On the third constellation 730, the value of the second radio signal sequence S _v,2 (k) corresponding to constellation point 00 may be an imaginary number j. The value of the second radio signal sequence S _v,2 (k) corresponding to the constellation point 01 may be -1, a real number. A value of the second radio signal sequence S _v,2 (k) corresponding to constellation point 10 may be a real number 1. A value of the second radio signal sequence S _v,2 (k) corresponding to constellation point 11 may be an imaginary number -j.

The second radio signal sequence S _v,2 (k) indicated by four constellation points on the third constellation 730 shown in FIG. 7C is a basic radio signal sequence S _v,1 ( For k), it may correspond to a result of performing a 3π/4 size rotation transformation operation on a complex plane. In other words, the four constellation points on the third constellation 730 are the result of shifting the four constellation points on the third final constellation 650 shown in FIG. 6D by a rotation angle of 3π/4 on the complex plane. may correspond to

In FIG. 7D , it can be seen that a fourth embodiment (hereinafter referred to as a fourth constellation) 740 of a constellation diagram for a second radio signal sequence S _v,2 (k) or a second radio signal is shown. On the fourth constellation 740, the value of the second radio signal sequence S _v,2 (k) corresponding to constellation point 00 may be a real number 1. A value of the second radio signal sequence S _v,2 (k) corresponding to constellation point 01 may be an imaginary number j. A value of the second radio signal sequence S _v,2 (k) corresponding to constellation point 10 may be an imaginary number -j. The value of the second radio signal sequence S _v,2 (k) corresponding to constellation point 11 may be -1, a real number.

The second radio signal sequence S _v,2 (k) represented by four constellation points on the fourth constellation 740 shown in FIG. 7D is a basic radio signal sequence S _v,1 ( For k), it may correspond to a result of performing a 3π/4 size rotation transformation operation on a complex plane. In other words, the four constellation points on the fourth constellation 740 are the result of shifting the four constellation points on the second final constellation 640 shown in FIG. 6D by a rotation angle of 3π/4 on the complex plane. may correspond to

It can be seen that FIG. 7E shows a second radio signal sequence S _v,2 (k) or a fifth embodiment (hereinafter referred to as a fifth constellation) 750 of a constellation for the second radio signal. On the fifth constellation 750, the value of the second radio signal sequence S _v,2 (k) corresponding to constellation point 00 may be a real number 1. A value of the second radio signal sequence S _v,2 (k) corresponding to constellation point 01 may be an imaginary number j. A value of the second radio signal sequence S _v,2 (k) corresponding to constellation point 10 may be an imaginary number -j. The value of the second radio signal sequence S _v,2 (k) corresponding to constellation point 11 may be -1, a real number.

The second radio signal sequence S _v,2 (k) indicated by four constellation points on the fifth constellation 750 shown in FIG. 7E is a basic radio signal sequence S _v,1 ( For k), it may correspond to a result of performing a rotation transformation operation of -π/4 size on a complex plane. In other words, the four constellation points on the fifth constellation 750 are obtained by shifting the four constellation points on the third final constellation 650 shown in FIG. 6D by a rotation angle -π/4 on the complex plane. result may apply.

It can be seen that FIG. 7F shows a second radio signal sequence S _v,2 (k) or a sixth embodiment (hereinafter referred to as a sixth constellation) 760 of a constellation for the second radio signal. On the sixth constellation 760, the value of the second radio signal sequence S _v,2 (k) corresponding to constellation point 00 may be a real number -1. The value of the second radio signal sequence S _v,2 (k) corresponding to the constellation point 01 may be an imaginary number -j. A value of the second radio signal sequence S _v,2 (k) corresponding to constellation point 10 may be an imaginary number j. A value of the second radio signal sequence S _v,2 (k) corresponding to constellation point 11 may be a real number 1.

The second radio signal sequence S _v,2 (k) represented by four constellation points on the sixth constellation 760 shown in FIG. 7F is a basic radio signal sequence S _v,1 ( For k), it may correspond to a result of performing a rotation conversion operation of -3π/4 size on a complex plane. In other words, the four constellation points on the sixth constellation 760 are obtained by shifting the four constellation points on the third final constellation 650 shown in FIG. 6D by a rotation angle -3π/4 on the complex plane. result may apply.

It can be seen that FIG. 7G shows a second radio signal sequence S _v,2 (k) or a seventh embodiment (hereinafter referred to as a seventh constellation) 770 of a constellation for the second radio signal. On the seventh constellation 770, the value of the second radio signal sequence S _v,2 (k) corresponding to constellation point 00 may be an imaginary number -j. A value of the second radio signal sequence S _v,2 (k) corresponding to the constellation point 01 may be a real number 1. The value of the second radio signal sequence S _v,2 (k) corresponding to constellation point 10 may be -1, a real number. A value of the second radio signal sequence S _v,2 (k) corresponding to constellation point 11 may be an imaginary number j.

The second radio signal sequence S _v,2 (k) represented by four constellation points on the seventh constellation 770 shown in FIG. 7G is a basic radio signal sequence S _v,1 ( For k), it may correspond to a result of performing a rotation transformation operation of -π/4 size on a complex plane. In other words, the four constellation points on the seventh constellation 770 are obtained by shifting the four constellation points on the third final constellation 650 shown in FIG. 6D by a rotation angle -π/4 on the complex plane. result may apply.

It can be seen that FIG. 7H shows a second radio signal sequence S _v,2 (k) or an eighth embodiment (hereinafter referred to as an eighth constellation) 780 of a constellation for the second radio signal. On the eighth constellation 780, the value of the second radio signal sequence S _v,2 (k) corresponding to constellation point 00 may be an imaginary number -j. The value of the second radio signal sequence S _v,2 (k) corresponding to the constellation point 01 may be -1, a real number. A value of the second radio signal sequence S _v,2 (k) corresponding to constellation point 10 may be a real number 1. A value of the second radio signal sequence S _v,2 (k) corresponding to constellation point 11 may be an imaginary number j.

The second radio signal sequence S _v,2 (k) indicated by four constellation points on the eighth constellation 780 shown in FIG. 7H is a basic radio signal sequence S _v,1 ( For k), it may correspond to a result of performing a rotation conversion operation of -3π/4 size on a complex plane. In other words, the four constellation points on the eighth constellation 780 are obtained by shifting the four constellation points on the second final constellation 640 shown in FIG. 6D by a rotation angle -3π/4 on the complex plane. result may apply.

In the first to eighth constellations 710, ..., 780 described with reference to FIGS. 7A to 7H, four constellations corresponding to the second radio signal generated according to the third embodiment of the radio signal generation method. The stores may all be located on the real axis or on the imaginary axis on the complex plane. The third embodiment of the radio signal generation method may be referred to as 'Axis QPSK (AQPSK) method' or 'AQPSK generation method'.

The second communication node may generate the second radio signal based on the second radio signal sequence S _v,2 (k) generated according to the third embodiment of the radio signal generation method. The second communication node may transmit the second radio signal generated based on the third embodiment of the radio signal generation method to the second communication node. The second communication node may receive the second radio signal. The second communication node may perform an estimation operation or an identification operation based on the second radio signal. Here, the second radio signal sequence S _v,2 (k) generated according to the third embodiment of the radio signal generation method is a real value (1, -1, etc.) or a pure imaginary value (j, -j, etc.) can have Due to this, when the second communication node performs an estimation operation or an identification operation based on the second radio signal generated according to the third embodiment of the radio signal generation method, a separate complex multiplication operation may not be required. Compared to the estimation operation or identification operation based on the first radio signal generated according to the second embodiment of the radio signal generation method described with reference to FIGS. 6B to 6D, the amount of calculation required (or operator number of circles) may be small, and computational complexity may be low. That is, the performance of an estimation operation or an identification operation performed by a communication node receiving the second radio signal generated according to the third embodiment of the radio signal generation method can be improved.

In addition, the second radio signal generated according to the third embodiment of the radio signal generation method may have the same or similar advantages as the first radio signal generated according to the second embodiment of the radio signal generation method.

4th embodiment of radio signal generation method

In one embodiment of the communication system, the first communication node may generate the third radio signal according to the fourth embodiment of the radio signal generation method. In a fourth embodiment of the radio signal generation method, a third radio signal may be generated based on one or more third radio signal sequences. One or more first radio signal sequences may be generated based on one or more binary sequences. One or more third radio signal sequences may be expressed as S _v,3 (k).

In one embodiment of the communication system, the third radio signal sequence S _v,3 (k) is a fourth binary sequence x ₄ (i), a fifth binary sequence x ₅ (i) and a sixth binary sequence x ₆ (i) can be created based on The fourth binary sequence x ₄ (i), the fifth binary sequence x ₅ (i), and the sixth binary sequence x ₆ (i) may correspond to PN sequences. For example, the third radio signal sequence S _v,3 (k) may be defined identically or similarly to Equation 7.

In Equation 7, the value of N may be 126 or 127. When N is 126, it can be considered that one of 127 subcarriers (eg, the central subcarrier) in the first subcarrier group described with reference to FIG. 5A is excluded from indexing. On the other hand, when N is 127, it can be considered that the center subcarrier among 127 subcarriers in the first subcarrier group is included in indexing and the value assigned to the center subcarrier is 0. The plurality of elements constituting the third radio signal sequence S _v,3 (k) defined based on Equation 7 may be divided into a first element group and a second element group based on the central subcarrier.

The fourth binary sequence x ₄ (i) and the fifth binary sequence x ₅ (i) may be defined based on different generator polynomials having a maximum degree of 6. A fourth binary sequence x ₄ (i) may be determined based on the fourth recurrence formula 'x ₄ (i+6)=[x ₄ (i+1)+x ₄ (i+0)] ₂ '. The fifth binary sequence x ₅ (i) is the fifth recursion 'x ₅ (i + 6) = [x ₅ (i + 5) + x ₅ (i + 2) + x ₅ (i + 1) + x ₅ ( i+0)] ₂ '. Meanwhile, the sixth binary sequence x ₆ (i) may be defined based on a generator polynomial having a maximum degree of 3. The sixth binary sequence x ₆ (i) may be determined based on the sixth recursive formula 'x ₆ (i+3)=[x ₆ (i+2)+x ₆ (i+0)] ₂ '. The recursive formulas and numbers shown in Equation 7 are only examples for convenience of description, and the fourth embodiment of the wireless signal generation method is not limited thereto. For example, the fourth binary sequence x ₄ (i), the fifth binary sequence x ₅ (i), and the sixth binary sequence x ₆ (i) may be generated in various ways other than the recursive equations shown in Equation 7.

In one embodiment of the communication system, the N elements constituting the third radio signal sequence S _v,3 (k) may be divided into a first group and a second group. For example, the third radio signal sequence S _v,3 (k) includes a first group (or first element group) consisting of N/2 elements and a first group consisting of N/2 elements. It can be generated based on 2 groups (or 2nd element group).

In one embodiment of the communication system, the first group may be denoted as S _v,3 [k] and the second group may be denoted as S _v,3 [k+N/2]. In the first group S _v,3 [k] and the second group S _v,3 [k+N/2], k may have a value greater than or equal to 0 and smaller than N/2. In Equation 7, the third radio signal sequence S _{v,3 (k)} based on the fourth binary sequence x ₄ (i), the fifth binary sequence x ₅ (i) and the sixth binary sequence x ₆ (i) Equation for calculating 1 group S _v,3 [k] 'S _v,3 [k]=1-2[x ₄ ([k+v ₄ ] ₆ 3)+x ₅ ([k+v ₅ ] ₆ 3 )+x ₆ ([k+v ₆ ] ₇ )] ₂ 'may correspond to a BPSK operation. Meanwhile, the second group S _v,3 [k+N/2] of the third radio signal sequence S _v,3 (k) may correspond to repetition of the first group S _v,3 [k]. Accordingly, the third radio signal sequence S _v,3 (k) including the first and second groups may have a real value of 1 or -1. Alternatively, in one embodiment of the communication system, the first group may be determined based on the intermediate sequence S _v,3 [k]. In this case, the second group may be determined based on repetitions of the intermediate sequence S _v,3 [k] (ie, S _v,3 [k+N/2]).

Theoretically, the maximum number of identification indices that can be distinguished based on the third radio signal sequence S _v,3 (k) is the fourth binary sequence constituting the third radio signal sequence S _v,3 (k) x ₄ (i) , the fifth binary sequence x ₅ (i) and the sixth binary sequence x ₆ (i) can be defined as a combination of all possible cyclic shift indexes. Each of the cyclic movement indices v ₄ and v ₅ associated with the fourth binary sequence x ₄ (i) and the fifth binary sequence x ₅ (i) may have a total of 63 values. The cyclic movement index v ₆ associated with the sixth binary sequence x ₆ (i) may have a total of 7 values. Therefore, theoretically, the maximum number of identification indices that can be distinguished based on the third radio signal sequence S _v,3 (k) may correspond to 63 × 63 × 7 = 16129. The third radio signal sequence S _v,3 (k) may have up to 63 cyclically distinct sequences.

, g₁=[333]_Ω, g₂=0, u=0과 같이 계산될 수 있다. 이 경우, 제4 이진 시퀀스 x₄(i), 제5 이진 시퀀스 x₅(i) 및 제6 이진 시퀀스 x₆(i)와 관련된 순환 이동 인덱스들은, v₄=0, v₅=[333]_Ω 및 v₆=

와 같이 계산될 수 있다. 이와 같이 계산된 순환 이동 인덱스들 v₄, v₅ 및 v₆의 값에 기초하여 제3 무선 신호 시퀀스 S_v,3(k)가 계산될 수 있다. 여기서, Ω는 Ξ에 기초하여 계산될 수 있다. 이를테면, Ω는 Ξ에 기초하여 수학식 8과 동일 또는 유사하게 계산될 수 있다.In one embodiment of the communication system, the value of the identification index v may be selected between 0 and Ξ-1. If v = 999 is selected, based on Equation 7, g = 333, g ₀ =

, g ₁ =[333] _Ω , g ₂ =0, u=0. In this case, the cyclic shift indices associated with the fourth binary sequence x ₄ (i), the fifth binary sequence x ₅ (i) and the sixth binary sequence x ₆ (i) are: v ₄ =0, v ₅ =[333] _Ω and v ₆ =

can be calculated as A third radio signal sequence S _v,3 (k) may be calculated based on the values of the cyclic movement indices v ₄ , v ₅ and v ₆ calculated as described above. Here, Ω can be calculated based on Ξ. For example, Ω can be calculated the same as or similar to Equation 8 based on Ξ.

In Equation 8, if Ξ = 1008, it can be determined as Ω = 48. If the value of Ξ is set to twice 1008 (ie, 2016), Ω = 48 may be determined. Based on the value of Ω determined based on Equation 8, values of the circular movement indices v ₄ , v ₅ and v ₆ may be determined. In Equations 7 and 8, 441 may correspond to the first reference value. Setting the first reference value to 441 is only an example for convenience of explanation, and the fourth embodiment of the radio signal generation method is not limited thereto.

The basic radio signal sequence S _v (k) generated based on Equation 1 and the generated third radio signal sequence S _v,3 (k) generated based on Equation 7 are compared identically or similarly to Table 5. can

Referring to Table 5, the number N of subcarriers mapped to the basic radio signal sequence S _v (k) after modulation may be 127, and the number of subcarriers mapped to the third radio signal sequence S _v,3 (k) after modulation. N may be 126. That is, the third radio signal sequence S _{v,3 (} k) generated according to the fourth embodiment of the radio signal generation method has a frequency resource of about 1.72 It may have the advantage of being able to support twice as many identification indices. In addition, since the third radio signal sequence S _v,3 (k) is generated based on linearly distinguishable sequences, the synchronization signal pairs generated based on the third radio signal sequence S _v,3 (k) The cross-correlation properties and their variability can be maintained.

Fifth Embodiment of Radio Signal Generation Method

In one embodiment of the communication system, the first communication node may generate the fourth radio signal according to the fifth embodiment of the radio signal generation method. In a fifth embodiment of the radio signal generation method, a fourth radio signal may be generated based on one or more fourth radio signal sequences. One or more first radio signal sequences may be generated based on one or more binary sequences. One or more fourth radio signal sequences may be expressed as S _v,4 (k).

In one embodiment of the communication system, the fourth radio signal sequence S _v,4 (k) is a seventh binary sequence x ₇ (i), an eighth binary sequence x ₈ (i) and a ninth binary sequence x ₉ (i) can be created based on The fourth radio signal sequence S _v,4 (k) may be generated based on the second intermediate sequence ζ (m), and the second intermediate sequence ζ (m) is the seventh binary sequence x ₇ (i), the eighth It can be defined based on the binary sequence x ₈ (i) and the ninth binary sequence x ₉ (i). The seventh binary sequence x ₇ (i), the eighth binary sequence x ₈ (i), and the ninth binary sequence x ₉ (i) may correspond to PN sequences. For example, the fourth radio signal sequence S _v,4 (k) may be defined identically or similarly to Equation 9.

In Equation 9, the value of N may be 126 or 127. When N is 126, it can be considered that one of 127 subcarriers (eg, the central subcarrier) in the first subcarrier group described with reference to FIG. 5A is excluded from indexing. On the other hand, when N is 127, it can be considered that the center subcarrier among 127 subcarriers in the first subcarrier group is included in indexing and the value assigned to the center subcarrier is 0.

The seventh binary sequence x ₇ (i) and the eighth binary sequence x ₈ (i) may be defined based on different generator polynomials having a maximum degree of 6. A seventh binary sequence x ₇ (i) may be determined based on the seventh recurrence formula 'x ₇ (i+6)=[x ₇ (i+1)+x ₇ (i+0)] ₂ '. The eighth binary sequence x ₈ (i) is the eighth recursion 'x ₈ (i + 6) = [x ₈ (i + 5) + x ₈ (i + 2) + x ₈ (i + 1) + x ₈ ( i+0)] ₂ '. Meanwhile, a ninth binary sequence x ₉ (i) may be defined based on a generator polynomial having a maximum degree of 3. A ninth binary sequence x ₉ (i) may be determined based on the ninth recursive formula 'x ₉ (i+3)=[x ₉ (i+2)+x ₉ (i+0)] ₂ '. The recursive formulas and numbers shown in Equation 9 are only examples for convenience of explanation, and the fifth embodiment of the wireless signal generation method is not limited thereto. For example, the seventh binary sequence x ₇ (i), the eighth binary sequence x ₈ (i), and the ninth binary sequence x ₉ (i) may be generated in various ways other than the recursive equations shown in Equation 9.

In Equation 9, a calculation formula 'ζ for calculating the second intermediate sequence ζ(m) based on the seventh binary sequence x ₇ (i), the eighth binary sequence x ₈ (i) and the ninth binary sequence x ₉ (i). _v (m)=1-2[x ₇ ([m+v ₇ ] ₆₃ )+x ₈ ([m+v ₈ ] ₆₃ )+x ₉ ([m+v ₉ ] ₇ )] ₂ ', It can correspond to an operation. The first group S _v,4 (N/2-1-k) of the fourth radio signal sequence S _v,4 (k) is based on the second intermediate sequence ζ (m) 'S _v,4 (N/2 -1-k)=ζ _v (k)'. The second group S _v,4 (k+N/2) of the fourth radio signal sequence S _v,4 (k) is 'S _v,4 (k+N/2) based on the second intermediate sequence ζ(m). )=ζ _v (k)'. That is, the second group of the fourth radio signal sequence S _v,4 (k) The second group S _v,4 (k+N/2) of the first group S _v,4 (N/2-1-k) It may correspond to symmetric repetition. Accordingly, the fourth radio signal sequence S _v,4 (k) including the first and second groups may have a value of 1 or -1.

In Equation 9, Ω can be calculated based on Ξ. Ξ may mean the number of distinguishable identification index v values. A total of Ξ identification indices can be identified by the fourth radio signal sequence S _v,4 (k) generated according to Equation 9. Here, Ω may be calculated the same as or similar to Equation 8 based on Ξ.

The generated fourth radio signal sequence S _v,4 (k) generated based on Equation 9 has the same or similar advantages as the third radio signal sequence S _v,3 (k) described with reference to Table 5. can That is, the fourth radio signal sequence S _{v,4 (} k) generated according to the fifth embodiment of the radio signal generation method has a frequency resource of about 1.72 It may have the advantage of being able to support twice as many identification indices.

Meanwhile, as the fourth radio signal sequence S _v,4 (k) is defined as in Equation 9, the time domain signal s _{v, 4 [n] of the fourth radio signal sequence S v,4} (k) is 10 can be determined.

Referring to the time domain signal s _{v,4 [n] of the fourth radio signal sequence S v,4} (k) expressed as in Equation 10, the signal s _{v,4 [} n] has only real components in the time domain can The first communication node transmitting the fourth radio signal may transmit only the real part when transmitting the fourth radio signal. Due to this, transmission complexity of the fourth radio signal may be reduced.

According to an embodiment of a method and apparatus for transmitting and receiving a radio signal in a communication system, performance of an estimation operation or an identification operation based on a radio signal transmitted and received between a transmission node and a reception node may be improved. A radio signal according to an embodiment of a method and apparatus for transmitting and receiving a radio signal in a communication system can support classification of more identification indices while using the same frequency resource. According to a radio signal according to an embodiment of a method and apparatus for transmitting and receiving a radio signal in a communication system, computational complexity for an estimation operation or an identification operation may be reduced. A radio signal according to an embodiment of a method and apparatus for transmitting and receiving a radio signal in a communication system may have lower transmission complexity while using the same frequency resource.

However, the effects that can be achieved by the embodiments of the method and apparatus for transmitting and receiving radio signals in a communication system are not limited to those mentioned above, and other effects not mentioned are described in the present disclosure from the configurations described in the specification of the present disclosure. will be clearly understood by those skilled in the art.

The operation of the method according to an embodiment of the present disclosure can be implemented as a computer readable program or code on a computer readable recording medium. A computer-readable recording medium includes all types of recording devices in which information that can be read by a computer system is stored. In addition, computer-readable recording media may be distributed to computer systems connected through a network to store and execute computer-readable programs or codes in a distributed manner.

In addition, the computer-readable recording medium may include hardware devices specially configured to store and execute program instructions, such as ROM, RAM, and flash memory. The program command may include high-level language codes that can be executed by a computer using an interpreter or the like as well as machine code generated by a compiler.

Although some aspects of the present disclosure have been described in the context of an apparatus, it may also represent a description according to a corresponding method, where a block or apparatus corresponds to a method step or feature of a method step. Similarly, aspects described in the context of a method may also be represented by a corresponding block or item or a corresponding feature of a device. Some or all of the method steps may be performed by (or using) a hardware device such as, for example, a microprocessor, programmable computer or electronic circuitry. In some embodiments, at least one or more of the most important method steps may be performed by such a device.

In embodiments, a programmable logic device (eg, a field programmable gate array) may be used to perform some or all of the functions of the methods described herein. In embodiments, a field-programmable gate array may operate in conjunction with a microprocessor to perform one of the methods described herein. Generally, methods are preferably performed by some hardware device.

Although the above has been described with reference to preferred embodiments of the present disclosure, those skilled in the art can variously modify and change the present disclosure within the scope not departing from the spirit and scope of the present disclosure described in the claims below. You will understand that you can.

Claims (20)

As a method of operating a first communication node in a communication system,
generating first and second binary sequences consisting of 2N elements;
generating a first intermediate sequence consisting of 2N elements based on the first and second binary sequences and a binary phase shift keying (BPSK) operation;
generating a first signal sequence composed of N elements based on an operation on the 2N elements constituting the first intermediate sequence;
mapping first modulation symbols generated by modulating the first signal sequence to N subcarriers; and
Transmitting a first signal composed of the mapped first modulation symbols;
The first and second binary sequences are generated based on generator polynomials having a maximum degree (p+1) and a first identifier for the first communication node;
Wherein p is a natural number, and N is a natural number having a value of (2 ^p -1),
Method of operation of the first communication node. The method of claim 1,
Generating the first intermediate sequence,
generating first and second circular movement indices based on the first identifier;
applying the first circular movement index to the first binary sequence;
applying the second circular shift index to the second binary sequence;
performing the BPSK operation on the sum of the first and second binary sequences to which the first and second cyclic shift indices are applied; and
Obtaining the first intermediate sequence corresponding to the result of the BPSK operation,
Method of operation of the first communication node. The method of claim 1,
Generating the first signal sequence,
multiplying 2k-th elements among the 2N elements constituting the first intermediate sequence by a first coefficient that is a real number;
multiplying 2k+1th elements among the 2N elements constituting the first intermediate sequence by a second coefficient that is a pure imaginary number;
performing a sum operation on the 2k-th elements multiplied by the first coefficient and the 2k+1-th elements multiplied by the second coefficient; and
obtaining k-th elements of the first signal sequence based on a result of the sum operation;
wherein k is an integer greater than or equal to 0 and smaller than N,
Method of operation of the first communication node. The method of claim 1,
Generating the first signal sequence,
multiplying 2k-th elements among the 2N elements constituting the first intermediate sequence by a first coefficient that is a real number;
multiplying a 2k+1th element among the 2N elements constituting the first intermediate sequence by a second coefficient that is a pure imaginary number;
performing a sum operation on the 2k-th elements multiplied by the first coefficient and the 2k+1-th elements multiplied by the second coefficient;
performing a rotation transformation operation by a first angle on a complex plane on a result of the sum operation; and
obtaining k-th elements of the first signal sequence based on a result of the rotation transform operation;
wherein k is an integer greater than or equal to 0 and smaller than N,
Method of operation of the first communication node. In claim 4,
The first angle is one of π / 4, -π / 4, 3π / 4, or -3π / 4,
Method of operation of the first communication node. The method of claim 1,
The first signal supports up to (2N + 1) ^two distinguishable values for the first identifier.
Method of operation of the first communication node. As a method of operating a first communication node in a communication system,
generating first and second binary sequences consisting of (N/2) elements, and a third binary sequence consisting of M elements;
generating a first intermediate sequence composed of (N/2) elements based on the first to third binary sequences and a binary phase shift keying (BPSK) operation;
generating first and second element groups each composed of (N/2) elements based on the first intermediate sequence;
generating a first signal sequence composed of N elements based on the first and second element groups;
mapping first modulation symbols generated by modulating the first signal sequence to N subcarriers; and
Transmitting a first signal composed of the mapped first modulation symbols;
The first and second binary sequences are generated based on generation polynomials having a maximum degree (p-1), and in each of the first to third binary sequences, a first identifier for the first communication node 1st to 3rd circular movement indices determined based on are applied, where p is a natural number, N is a natural number having a value of ( ^2p -2), and M is a value less than or equal to (N/2). is a natural number having
Method of operation of the first communication node. The method of claim 7,
Generating the first intermediate sequence,
determining the first to third circular movement indices based on the first identifier;
applying the first circular movement index to the first binary sequence;
applying the second circular shift index to the second binary sequence;
applying the third circular movement index to the third binary sequence;
performing the BPSK operation on the sum of the first to third binary sequences to which the first to third circular movement indices are applied; and
Obtaining the first intermediate sequence corresponding to the result of the BPSK operation,
Method of operation of the first communication node. The method of claim 8,
Determining the first to third circular movement indices,
determining a first variable g based on the value of the first identifier;
determining a second variable Ω based on the number of possible values of the first identifier; and
determining the first to third circular movement indices based on the first variable g, the second variable Ω and a first reference value t and one or more modulo operations;
The g, the Ω and the t are natural numbers,
Method of operation of the first communication node. The method of claim 9,
The second circular movement index is determined based on a t-modulo operation and an Ω-modulo operation for the first variable g,
Method of operation of the first communication node. The method of claim 8,
The first signal supports up to (M × N × N) distinguishable values for the first identifier,
Method of operation of the first communication node. The method of claim 7,
The (N/2) elements constituting the first element group are represented by k-th elements, and the (N/2) elements constituting the second element group are represented by (N/2+k)-th elements. represented by elements,
Generating the first and second element groups,
obtaining the k-th elements of the first element group based on k-th elements among the (N/2) elements constituting the first intermediate sequence; and
obtaining the (N/2+k)th elements of the second element group based on the kth elements among the (N/2) elements constituting the first intermediate sequence; ,
The N elements constituting the first signal sequence include the (N/2) elements constituting the first element group and the (N/2) elements constituting the second element group. consists of
wherein k is an integer greater than or equal to 0 and smaller than (N/2);
Method of operation of the first communication node. The method of claim 7,
The (N/2) elements constituting the first element group are represented by (N/2-1-k)th elements, and the (N/2) elements constituting the second element group are It is represented by (N/2+k)th elements,
Generating the first and second element groups,
obtaining the (N/2-1-k)th elements of the first element group based on the kth elements among the (N/2) elements constituting the first intermediate sequence; and
obtaining the (N/2+k)th elements of the second element group based on the kth elements among the (N/2) elements constituting the first intermediate sequence; ,
The N elements constituting the first signal sequence include the (N/2) elements constituting the first element group and the (N/2) elements constituting the second element group. is composed of
wherein k is an integer greater than or equal to 0 and smaller than (N/2);
Method of operation of the first communication node. The method of claim 13,
The first modulation symbols mapped to the N subcarriers form a centrally symmetrical structure around a first reference subcarrier of the N subcarriers.
Method of operation of the first communication node. The method of claim 13,
The first signal has only real components in the time domain,
Method of operation of the first communication node. As a first communication node in a communication system,
Including a processor,
The processor may cause the first communication node to:
generate first and second binary sequences consisting of (N/2) elements, and a third binary sequence consisting of M elements;
generate a first intermediate sequence consisting of (N/2) elements based on the first to third binary sequences and a binary phase shift keying (BPSK) operation;
based on the first intermediate sequence, create first and second element groups each consisting of (N/2) elements;
generate a first signal sequence composed of N elements based on the first and second element groups;
mapping first modulation symbols generated by modulating the first signal sequence to N subcarriers; and
operative to cause transmission of a first signal consisting of the mapped first modulation symbols;
The first and second binary sequences are generated based on generation polynomials having a maximum degree (p-1), and in each of the first to third binary sequences, a first identifier for the first communication node 1st to 3rd circular movement indices determined based on are applied, where p is a natural number, N is a natural number having a value of ( ^2p -2), and M is a value less than or equal to (N/2). is a natural number having
A first communication node. The method of claim 16
When generating the first intermediate sequence, the processor causes the first communication node to:
determine the first to third circular movement indices based on the first identifier;
apply the first circular movement index to the first binary sequence;
apply the second circular shift index to the second binary sequence;
apply the third circular shift index to the third binary sequence;
performing the BPSK operation on a sum of the first to third binary sequences to which the first to third circular shift indices are applied; and
further cause obtaining the first intermediate sequence corresponding to a result of the BPSK operation;
A first communication node. The method of claim 17
When determining the first to third circular movement indices, the processor causes the first communication node to:
determine a first variable g based on the value of the first identifier;
determine a second variable Ω based on the number of values the first identifier can have; and
further cause determining the first to third circular movement indices based on the first variable g, the second variable Ω and a first reference value t and one or more modulo operations;
The g, the Ω and the t are natural numbers,
A first communication node. The method of claim 18
The second circular movement index is determined based on a t-modulo operation and an Ω-modulo operation for the first variable g,
A first communication node. The method of claim 19
The first signal supports up to (M × N × N) distinguishable values for the first identifier,
A first communication node.

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